1. Field of the Invention
The present invention relates to a light emitting system that can be controlled on a wireless basis.
2. Related Background Art
Japanese Patent Application Laid-Open No. 54-115224 proposes a wireless flash photography system that performs a signal communication only by radio wave. The wireless flash photography system disclosed in Japanese Patent Application Laid-Open No. 54-115224 transmits a carrier wave signal in advance before shutter release of a camera and increases the energy of the carrier wave signal at the time of releasing the-shutter in order to shorten the time up until the light emission.
However, the wireless flash photography system disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 54-115224 consumes a large amount of electric power, since it transmits the carrier wave signal continuously before the shutter release.
In view of this, the above-mentioned system is susceptible to improvement to enable quick light emission at the time of the release of a camera shutter without continuously emitting a carrier wave signal.
According to one aspect of the invention there is provided a light emitting system that performs wireless communication by a signal other than light and wireless communication by light, and a transmitting apparatus and a receiving apparatus that constitute such a light emitting system. The transmitting apparatus transmits a light emission data signal for setting a light emitting condition(s) of an illuminating apparatus to the receiving apparatus by a signal other than light on a wireless basis, and transmits a light emission start signal for starting light emission by light on a wireless basis. The receiving apparatus causes the illuminating apparatus to perform a light emission preparation operation based on the light emission data signal, and causes the illuminating apparatus to emit light based on the light emission start signal. With the invention, it is possible to suppress consumption of electric power required for transmission and to shorten the delay time between inputting of a light emission command to the transmitter and light emission of the receiver.
According to anther aspect of the invention, there is provided a light emitting system that performs wireless communication by a signal other than light and wireless communication by light, and a transmitting apparatus and a receiving apparatus that constitute such a light emitting system. The transmitting apparatus transmits a light emission data signal for setting a light emitting condition(s) of an illuminating apparatus to the receiving apparatus by a signal other than light and by light, on a wireless basis, and transmits a light emission start signal for starting light emission by light on a wireless basis. A first receiving apparatus causes a first illuminating apparatus to perform a light emission preparation operation based on the light emission data signal that has been transmitted by light, and causes the first illuminating apparatus to emit light based on the light emission start signal. A second receiving apparatus causes a second illuminating apparatus to perform a light emission preparation operation based on the light emission data signal that has been transmitted by the signal other than light, and causes the second illuminating apparatus to emit light based on the light emission start signal. Since the light emission data signal is communicated by light and a signal other than light on a wireless basis and the light emission start signal is transmitted by light on a wireless basis, it is possible to cause illuminating apparatus to emit light appropriately, even if a receiver that receives the light emission data by the signal other than light and receives the light emission start signal by light and a receiver that receives the light emission data as well as the light emission start signal by light are used in combination.